1. Field of the Invention
The present invention relates to a method of and an apparatus for displaying teletext information for a wide-screen television receiver. More particularly, the present invention relates to a teletext information displaying method and an apparatus therefor which can selectively display desired teletext information on a screen having a 16.times.9 aspect ratio.
2. Description of the Prior Art
A wide-screen television receiver has a display screen having an aspect ratio (A.R.) of 16.times.9, and a user can enjoy watching television as if the user was watching a movie in a theater.
FIG. 1 is a block diagram of a conventional apparatus for displaying teletext information, employed in a wide-screen television receiver. According to the apparatus of FIG. 1, a composite video signal, which is received through an antenna ANT and then inputted to a tuner 10, is converted into an intermediate frequency (IF) signal in an intermediate frequency processing circuit 20. The IF composite video signal from the IF processing circuit 20 is converted into R, G, and B color signals in a video processing circuit 40, and the R, G, and B signals are supplied to a switching circuit 60.
Also, the IF composite video signal outputted from the IF processing circuit 20 is supplied to a teletext extraction section 31 in a teletext processing circuit 30 and a teletext signal (i.e., character signal) is extracted from the composite video signal by the teletext extraction section 31. The extracted teletext signal is decoded by a teletext information processing section 32 and the decoded teletext signal is supplied to a character generator 50. At the same time, the teletext information decoded by the teletext information processing section 32 is stored in a memory 33.
If data for displaying a certain page of the teletext information is inputted to the teletext processing circuit 30, the teletext information processing section 32 scans the inputted data and provides the same to the character generator 50. The character generator 50 outputs to the switching circuit 60 R, G, and B signals for displaying the teletext information in accord with the current television display format and a switching control signal FB for controlling the operation of the switching circuit 60. The teletext signal is thereby displayed on a cathode ray tube 70.
The character generator 50, under the control of a system controller (microcomputer, not illustrated), outputs R, G, and B signals of the teletext page selected among the pages of the teletext data stored in the memory as shown in FIG. 2, and thus the information of the corresponding page is displayed on the cathode ray tube 70 with the size of 40 columns.times.24 lines.
However, the conventional teletext information displaying method or apparatus as described above has the disadvantage that when the teletext information having a 4.times.3 A.R. is displayed on a 16.times.9 A.R. screen, the teletext picture is distorted by expansion in the horizontal direction.
Meanwhile, FIG. 3 is a block diagram of another conventional apparatus for displaying teletext information for a wide-screen television receiver. A teletext page received and processed by the apparatus of FIG. 3 is displayed on a screen as shown in FIG. 4.
Referring to FIG. 3, if a user enters a desired page information data, a microcomputer 34 receives (i.e., scans) the entered data and supplies command data for displaying the corresponding teletext page data to a control section 35.
If the display command data is inputted from the microcomputer 34, the control section 35 supplies the teletext page data to a receiving section 36 so that the receiving section 36 receives a teletext code and the teletext data outputted from a teletext extraction section 31 which extracts the teletext signal included in an input video signal. At the same time, the control section 35 supplies write/read data to a memory interface section 37 so that the teletext page data received through the memory interface section 37 is stored in or read out from a page memory 33. Accordingly, the input teletext page data is supplied to the character generator 50, so that the teletext page data is displayed on the full screen as shown in FIG. 4.
However, the conventional teletext information displaying apparatus as described above has the drawback that a user must continually enter page information data in order to search teletext pages.